What is SQL and What are its Main Components?

Are you a fresher planning to pursue SQL Courses for a better career or an experienced professional revising your SQL skills before an SQL developer interview? This blog discusses Structured Query Language (SQL), including the fundamentals, components and characteristics. It can help you with the interview preparation process.

SQL is a computer language that acts as a bridge between humans and databases. It allows humans to communicate with databases in a structured and efficient way to extract and manage valuable information. Various platforms like Python or R can later analyse this extracted data. Using SQL, users can manage numerous data transactions where large volumes of data are written simultaneously. By executing queries, SQL can create, update, delete and retrieve data in databases like MySQL, Oracle, PostgreSQL, etc. 

Please read the blog further to learn more about What is SQL, its characteristics, and main components. After learning the basics, it would be best to practice SQL interview questions to help you prepare better for your interview.

What is SQL?

Structured Query Language (SQL) is an important part of working with Relational Database Management Systems (RDBMS). SQL helps people communicate with databases. It facilitates a standard way of defining and manipulating data from such systems. SQL allows the execution of database operations, which could include modifying the basic structure of the database with commands such as CREATE, ALTER, and DROP, retrieving data from the database using SELECT command, and modifying data using INSERT, UPDATE, and DELETE commands.

Its adaptability allows for the creation of stored procedures, triggers, and views, improving database functionality and efficiency. Because SQL is declarative, users may define desired results without going through procedural processes, making database operations more efficient and scalable. Its extensive use in many industries highlights how crucial it is to data management, analysis, and decision-making procedures.

What are the Characteristics of SQL?

• Anybody can use SQL even if they have significantly less programming experience.
• Users can create and replace databases in SQL without difficulty. It is a process that takes time.
• It is a non-procedural language, which is primarily based totally on ANSI standards. 
• SQL does not have a continuation individual any longer
• It uses a termination individual to execute instructions immediately. It also uses features to carry out a few formatting.
• SQL uses functions to perform some formatting. 

Five Major Components of SQL

As you have already learned about SQL, it is time to understand its top five significant components.

Data Definition Language (DDL)

DDL consists of SQL commands that specify the schema or database structure. It is used to create and alter the structure of database objects in databases and merely deals with descriptions of the database schema. DDL offers a collection of definitions that outline the access techniques and storage structure that the database system uses.

Data Manipulation Language (DML)

DML is a computer programming language that adds, removes, and edits database data. In SQL, the data manipulation language comprises the SQL-data change statements, which alter stored data but not the database table schema. Once the database has been created and the schema has been specified, DML-expressed procedures can be used to manipulate the data. 

Data Query Language (DQL)

DQL is a basic sub-language of SQL statements. It is used to conduct inquiries on data contained in schema objects. The commands DQL uses the SELECT statement to get data from the database and manipulate it as we want. 

Transactional Control Language (TCL)

TCL commands manage database transactions. Using DML statements, we can alter the changes made to the data in a table.

Data Control Language (DCL)

DCL is a programming language used to manage who has access to the data kept in a database. It is employed to manage authorisation privileges in the database. The privileges required for performing all the database actions, including creating sequences and table views, require rights. 

Conclusion

SQL is a programming language that helps data professionals retrieve and manipulate data from databases. If you are an SQL enthusiast, you have several opportunities worldwide. The job market for SQL professionals looks good and is expected to grow in the coming years. Now, with this detailed guide, we hope you got all the information you sought.